Air or gas lift valves



Sept. 27, 1960 c. R. cANALlzo AIR OR GAS LIFT VALVES 2 Sheets-Sheet 1Filed Jan. 11, 1957 1NvENToR Carlos R. Canallzo vATTORNEY Il In Sept.27, 1960 c. R. cANALlzo AIR 0R GAS LIFT VALVES 2 Sheets-Sheet 2 FiledJan. l1, 1957 Fig.7

d/IS

INVENTOR F'Q- Carlos R. Conolizo BY Zmmw ATTORNEY United States PatentAIR R GAS LIFI VALVES Carlos 'R. `Canalizo, Dallas, Tex., assignor toOtis Engineering Corporation, Dallas, Tex., a corporation of Texas FiledJan. 11, 1957, ser. No. 633,135 11 claims. (ci. 137-155) This inventionrelates to air or gas lift valves for use in oil wells and the like forcontrolling the admission of gas or air into a column of uid in the wellto lift the column and aid in flowing the fluid from the well.

In conventional gas lift Vsystems the Well equipment includes a' stringof relatively small pipe called the tubing which is inserted inside alarger diameter pipe Vcalled the casing Gas or air is introduced undercontrolled pressures and volumes into the annular space between thetubing and the casing and is injected through suitable gas lift valveslocated at spaced points along the tubing into the column of oil insidethe tubing in order to lift the oil to the surface.

The gas lift valves may be mounted exteriorly of the tubing string andcommunicate with the interior of the tubing through suitable ports inthe wall of said tubing, or the valves may be removably mounted inspecially prepared landing nipples wherein the valve is positionedlaterally of the principal tubing bore and in which suitable gas inletports are provided so that the tubing bore remains open for the passageof other -tools therethrough. Alternatively, the valves may beremovably,

positioned in the main tubing bore, or they may be fixed in position inthe main tubing bore. v

Conventional gas lift valves generally include a circular valve seathaving ay central lbore or orifice through which the lifting gas passesfrom the annular space and into the tubing. A valve disc or plug isarranged to cooperate with the seat to open and close the bore of saidseat for controlling the passage of gas therethrough. The movements ofthe disc or plug are ordinarily controlled by a suitable loadingmechanism, such as a coil spring or a flexible bellows, or both, whichare adapted to provide the necessary loading on the valve disc tocontrol the pressures at which opening and closing of the valve willtake place.

Such conventional gas liftvalves are subject to many disadvantages. Theyare necessarily relatively complicated in construction, requiring arelatively large number of parts, including moving parts. The plug andseat members are subject to erosion and cutting out due to thenecessarily high velocities of the gas passing through the valve,particularly in the initial opening and nal closing s-tages. As aresult, conventional plugs and seats are made of metal and requirehighly finished and specially hardened seating surfaces. The bellows andsprings are subject to corrosion and fatigue and must therefore beconstructed of specially alloyed expensive materials.

Further, conventional gas lift valves have a limited valve opening area,and the opening of the movable valve member is limited to the movementof a bellows or spring. Conventional gas lift valves are universallysubject to the effect of the pressure existing within the tubing; thatis, the opening pressure of a conventional gas lift valve varies withthe pressure existing in the tubing. Most conventional gas lift valvesare also subject to wire-drawing; that is, the valve does not com- ICCPatented Sept. 27, 1960 gas lift valve construction which will eliminateor greatlyv obviate the several disadvantages inherent in .conventionaltypes of gas lift valves.

A principal object of this invention is to provide a gas lift valvewhich may be mounted exteriorly of the tubing ystring or which may beremovably installed in a landing nipple in the -tubing string.

A further object of the invention is to provide a valve structure whichincludes pressure loaded valve closure or control sleeve yconstructed ofa flexible resilient material which is normallyy in a closed positioncontacting gas admission ports in a valve housing but which iscontractable radially to'an open position away from said gas admissionports.

A still further object of the invention is to provide a valve s-tructurein which the closure elements have no metal-to-metal engaging surfaces.

An additional object of the invention is to provide a gas lift valve ofthe type described and which includes an auxiliary check valve meansadapted to prevent back flow of fluid from the tubing, the check valvebeing constructed of -resilient flexible material. Y v

Another object of the invention is to provide a gas lift valve whoseclosure elements do not depend on a fine iinish and close tolerances,whereby the valve may function properly even though the closure elementssuffer corrosion or erosion.

Still another object of the invention is to provide a gas lift valvewhich opens and closes at a predetermined pressure completelyindependently of the pressure existing within the tubing. l .l

An additional object of the invention is to provide a. gas lift valvewhich opens and closes positively at a predetermined pressure withoutany wire-drawing effects.

Additional objects and advantages of the invention will be Areadilyapparent from the reading of the following `description of a deviceconstructed in accordance with the invention, and reference to theaccompanying drawings thereof, wherein:

Figure 1 is an elevation view showing a portion of a Well with the valvemounted exteriorly of the'tubing lstring of the well;

Figure 2is a detailed view, partly in section, of the valve of Figure l,whe-rein the control sleeve is shown i closed posi-tion; n

Figure 3 is an enlarged fragmentary view, partly in section, of thevalve of Figures 1 and 2, wherein the control sleeve is shown in openposition;

Figure 4 is a view, partly in section and partly in elevation, of avalve constructed in accordance with the invention and installed in aspecially prepared nipple in the tubing string;

Figure 5 is an enlarged view, partly in section, of the lower part ofthe valve of Figure 4, wherein the control sleeve is shown in closedposition;

Figure 6 is an isometric view of the retainer for the lower end of thecontrol sleeve;

IFigure 7 is an isometric view of the check valve body or spider; and

Figure 8 is an isometric view of the reinforcing sleeve for the checkvalve seal element. A

Referring now particularly to Figures 1 `through 3 of the drawings, thevalve 10 is shown mounted on the exterior of a specially prepared nipple11 which is connected by couplings 12 in la string of well pipe ortubing (not shown) and which is disposed in a string of well casing C.The tubing string and the casing string may extend from a producingformation to the surface of the ground rangl,

may be provided with a packer (not shown) below the valve in a mannerwell known in the art.

The valve includes a tubular chamber 13 whose upper end is closed by acharging sub 14 having a charging valve 15 threaded in an opening in theupper end of said s ub and a plug 16 threaded into the sub above thecharging valve. The charging valve permits flow therethrough into thechamber but prevents reverse flow from the chamber. The charging valvemay be similar to the well known pneumatic valves used for introductionof the air into pneumatic tires. A protective cap 17 may be threadedonto the upper end 18 of the sub to protect the plug from damage. Y

A tubular body 19 is threaded into the lower end of the chamber and isprovided with a plurality of lateral gas entry slots 20 through its wallfor a purpose to be more fully hereinafter described.V A tubular lowersub 21 is threaded into the lower end of the body 19 and is providedwith threads 22 at its lower end for attachment of the Valve to aninjection lug 23 which is welded or otherwise affixed to the nipple 11.An injection passage 24 in the injection sub communicates with aninjection port 25 in the wall of the nipple whereby fluid communicationis provided through the injection passageway from the valve to theinterior of the tubing, and the welds 26 attaching the lug to the nippleprevent leakage between the lug and the nipple. A protective guide lug27 may be welded to the exterior of the nipple above the upper end ofthe valve to prevent damage to the valve as the tubing is lowered intoor pulled from the well.

A valve mandrel 28 having a bore 29 opening to its upper end has mountedon its lower end a tubular control sleeve or closure member 30 closed atits lower end, and constructed of resilient material such as rubber,neoprene, or the like. The outer surface of the closed lower end of thecontrol sleeve approximates a hemisphere. The control sleeve is held inposition on the lower end of the valve mandrel by an inwardly extendingannular flange 31 at the upper end of said control sleeve whichresiliently engages an upwardly facing annular shoulder 32 on the outersurface of the lower portion of the valve mandrel. The valve mandrel isinserted through the lower end of 'the bore of the body andprotrudesupwardly therethrough and is held in place in said body by theengagement of an external annular shoulder 33 on the mandrel with aninternal annular shoulder 34 Vformed by a counterbore 35 in the body andby a nut 36 and a lock nut 37 threaded to the upper end of the mandreland engaging the upper end of the body. An O-ring seal means 38 in anannular groove 39 in the external surface of the valve mandrel sealsbetween the mandrel and the counterbore 35 of the body. The outersurface of the valve mandrel is relieved at its lower end at 40 toprovide a space 41 between the lower outer surface of the mandrel andthe inner surface of the control sleeve, and lateral ports 42 throughthe wall of the mandrel provide communication between the bore 29 of themandrel and said space.

The inner diameter of the body 19 below the counterbore 35 is furtherenlarged at 43, providing a downwardly facing shoulder 43a thereat, andthis enlarged inner diameter includes the area in which the slots 20 arelocated. The control sleeve is of such free diameter as to normallyresiliently engage the enlarged surface 43 and the ports 20 to closesaid ports and to function in a manner to be hereinafter more fullydescribed.

A retainer or support member 44 having a concave upper surface 45conforming to the convex lower outer surface of the control sleevesupports the lower end of said control sleeve and is in turn supportedon the upper end of the lower sub 21. A plurality of circumferentiallyspaced longitudinal slots 46 in the outer surface of the retainerprovide passages for the flow of fluids therepast.

A check valve 47 is threaded into the upper end of the sub 21 andincludes a check valve body or spider 48 having a cup-shaped opening 49in its lower end. A tubular resilient check valve seal element or cup 50constructed of rubber, neoprene, or the like, has an outwardly inclinedlip 51 at its lower end normally resiliently engaging the bore wall ofthe sub 21. The seal element or cup is secured in the cup-shaped openingin the check valve body by a cap screw 52 threaded into said body withits head engaging an inwardly extending annular ange 53 at the upper endof said element. A resilient tubular reinforcing sleeve 53a having aplurality of depending ngers 53b formed by a plurality of upwardlyextending slits 53e is disposed around the check valve element andwithin the cup-shaped opening of the check valve body whereby the`element is reinforced by the fingers of said sleeve.

A plurality of circumferentially spaced longitudinal slots 54 in theouter surface of the check valve body provide uid iiow passages past thecheck valve body. The construction of the check valve thus permits ow offluid or lifting gas downwardly through the slots 54 and thence past thelip of the seal element, said lip exing inwardly to permit such flow.Flow of fluid or gas in an upward direction is prevented by the sealingengagement of the lip 51 of the element with the bore wall of the lowersub. The lip of the seal element is normally in closed position incontact with said bore wall of the lower sub, but readily ilexesinwardly to permit downward ow therepast. The lower end of Ithecup-shaped opening of the body is beveled downwardly and outwardly at55. The ngers of the reinforcing sleeve will usually bridge the openingsof the slots 54 in the check valve body to prevent extrusion of thevalve element in said slots when the pressure below the check valve isgreater than that above said check valve.

In operation, before the valve is installed in position on the nipple 11and before the tubing T has been lowered into the well, the chamber 13is charged with a pneumatic fluid such as air or gas to a predeterminedoperating pressure through the charging Valve 15. The plug 16 and theprotective cap 17 may be installed to seal off any leakage` through thecharging valve and to protect the upper end of the charging valve. Thegas under pressure flows through the bore 29 of the valve mandrel andthrough the ports 42 of said mandrel into the space 41 between themandrel and the closure member or control sleeve 30, thereby holdingsaid control sleeve in closing or sealing contact with the bore wall ofthe body 19 across the slots 20. It will be evident that -as long as thepressure of the exterior of the gas lift valve is less than that on theinterior 'of the chamber and the closure member 30, the closure memberwill be maintained in closed position in sealing contact across theslots 20 (Figure 2), forming a tight closure therefor. The slots aresufficiently narrow that the material of the valve member does notextend therethrough to any material degree. The lower end of the closuremember or control sleeve is retained in position on the lower end of themandrel against the pressure of the charging gas, as previouslyindicated, by the concave upper surface of the retainer 44 and by theconfinement of the flange 31 of the control sleeve between the upwardlyfacing shoulder 32 on the mandrel and the downwardly facing shoulder 43ain the bore of the body. y

With the valve thus pre-set or pre-loaded for the desired operatingpressure, it is installed in position on the mandrel 11 and the tubingis lowered into position in the casing of the well. Oil or otherformation liquid will enter the lower open Vend (not shown) of thetubing and rise to the level therein to an extent determined by theformation pressure. It is noteworthy that the formation liquid cannot owoutwardly through the gas lift valve, as the check valve 47 closes offupward flow through the body from the passage 24 by the sealingengagement of the lip 51 of the check valve element 50 with the bore ofthe sub 21.

If the formation pressure is such that the formation fluids will notflow upwardly to the Surface, 'gas `or air treferred to as gasgenerally) in sufcient pressures will be in'tldued into the annular spacbetween the tubing string and the casing string in order for the gas tobe injected through the gas lift valve into the column of uid in thetubing. While the pressure of the gas is below the pressure of thecharging gas in the chamber of the valve, the control sleeve remains inits normal position in which it closes the slots 20 of the valve aspreviously described. v 1 `As soon as the pressure of the'injection gasexceeds the pressure of the charging gas, the control sleeve-or clo'suremember 30 is forced inwardly away from the bore wall of the body 19 andthe slots `20 therein, and the injection gas ows inwardly through saidrslots asshown by the arrows in Figure 3. The gas then ows' downwardlythrough the slots 46 of the retainer member andvthrough the longitudinalslots 54 of the check valve body or spider 48 and past the outside ofthe check valve element, resiliently flexing the lip 5-1 thereofinwardly from its sealing engagement with the bore wall of the sub. Thegas further flows downwardly into the injection passage 24 of theinjection lug and into the interior of the tubing. p The force andvolume of gas thus introduced will lift the column of iluid standingabove the valve to the surface or will aerate the column of uid to solighten said column that it may be lifted by its formation pressure. Assoon as the gas pressure in the annular space between the tubing and thecasing falls below the pre-set operating pressure of the valve, that is,the pressure of the loading gas within the chamber 13 and within thecontrol sleeve or closure member 30, the valve closure member will againmove to its normally closed position engaging the -bore wall of the body19 to close the slots 20, and the check valve 47 will close to preventany back ow of iluid through the valve.

A number of gas lift valves may be employed at spaced intervals alongthe tubing string. In this event the valves may be set to operate atdifferent annulus pressuresor they may be set to operate at the samepressure, in accordance with well established iluid lifting practices.

It will be seen that a gas lift valve has been illustrated and describedwhich isreadily mountable on the exterior of a tubing string. The valvewill be seen to involve no metal-to-metal sealing surfaces in its movingparts, the closure member being made of a resilient material, wherebyhigh preoision of machining is not necessary on the valve seat parts.The resilient material of the valve closure member may be of a type toresist the corrosive effects of the injection gas or of the well fluids,and the resilient material of the closure member is less subject toerosion than is a metal closure element.

y It will be seen that the amount of movement of the valve member toopen the slots 20 is small, and the volumeV of the loading chamber maybe adjusted so this change in volume as the valve is opened isnegligible compared to the total volume of the chamber. Accordingly, 'itwill be seen that the valve is able to open and close substantiallyinstantaneously as the injection gas pressure exceeds or falls below,respectively, the pre-set or pre-loaded oper'- ating pressure of thevalve, there being no differential areas subjected to diierent pressureswithin and without the tubing, whereby the so-called tubing eiectpresent in metallic valves is eliminated.

It will further be seen that the valve admits of accurate operation andcontrol, as the wear, corrosion or erosion of any of the operating partshas little or no eect on their operation. The absence of metal bellowsor springs eliminates the undesirable effects inherent with suchelements due to their fatigung or relaxing through repeated ilexure ordeformation.

It will also be seen that the valve area is much larger than that ofconventional gas lift valves, .as the area of the slots `20 is muchgreater than the opening through the normalvalve-and-seat arrangementused in conventional valves. Itis apparent that the valve is not subjectto wire-drawing, as the control sleeve .moves between closedand openpositions as soon as the annulus pressure exceeds or becomes less thanthe predetermined charging pressure of the valve.

It will additionally be seen that the valve is not subject to the eiectof pressure within the tubing and the control sleeve opens at the samepressure whether or not pressure exists within the tubing. It is alsoevident that when the check valve is used no reverse flow can take placefrom the inside of the tubing through the valve tothe annular spacebetween the -tubng string and the casing string.

Figure 4 shows the gas lift valve removably installed in a speciallyprepared housing or landing nipple of atubing string.

The specially prepared housing or landing nipple 70 is of a charactergenerally referred to as the olset type and is threadedly connected in atubing string T. This landing nipple is provided with a landing sectionor pocket 71 which is laterally offset from the bore through the nipplewhereby a full opening as large as the bore through the tubing isprovided past the pocket, This pocket may be made up of an upper section72 and a lower section 73 welded together and having a commonlongitudinal bore 74 openingupwardly. The pocket may be eccentricallyatlixed in the wall of the nipple as by welds 75. An internal annularrecess 76 near the upper'end of the upper pocket section provides alocking recess for engagement by a lock dog on the removable gas liftvalve, as will be more fully explained. j

A plurality of ports 77 through the wall of the lower pocket sectionprovide fluid communication between the exterior of the nipple and theinterior of the pocket, and a discharge port 7'8 at the lower end of thepocket pro- .vides liuid communication therethrough between the bore thevalve 79' are therefore assigned like numbers to those of the valve 10.Y

A locking mandrel 80 is connected to the upper end of the charging sub14 by means of the threads 18, in lieu of the protective cap 17 shown inFigures l and 2. 'I'he locking mandrel includes an expansible andretractible 4latch means 81 of -a character to engage in the lockingrecess of the pocket. An external annular ange 82 near the upper end ofthe locking mandrel is engageable with the upper end of the pocket tolimit downwarld movement of thevalve in the pocket, and a gripping head*83 is engageable by a suitable running or retrieving tool (not shown)for inserting the valve into lor removing it from the pocket. A

A .guide and flow cap 84 attached by means of the threads 22 to thelower end of the lower sub 21 is provided with a plurality of ow ports85 therethrough whereby fluids or gas passing downwardly through thevalve may emerge therethrough from the lower end of the valve. The lowersurface of the liow cap is downwardly and inwardly beveled at 86 wherebythe valve may be easily inserted into the pocket.

An upper sealing means 57, shown to be of the V type, is disposed on theouter surface of the body 19l above the ports 20 and is retained thereonbetween an upwardly facing external annular shoulder 58 on the body andthe lower end of the chamber 13. A similar lower sealing means 59 is`disposed on the outer surface of the lower sub 21 between a downwardlyfacing external annular shoulder 60 on said sub and the upper end of theow cap 84. These sealing means are adapted'Y to sealingly engage thebore wall 87 of the pocket above and below the ports 77, as will behereinafter more fullyexplained.

Figures l through 3, -the plug 16 is installed in the upper end ofthecharging sub, and the locking mandrel is attached thereto. The gaslift valveand locking mandrell assembly is lthen lowered into the tubingstring in the well known manner by means of a flexible line loweringmechanism (not shown) and is moved laterally in the landing nipple in amanner well lknown in the ar-t to position the valve into the pocket.The valve is lowered in the pocket until its downward movement isstopped by the engagement of the flange 82 of the locking mandrel withthe upper end of the pocket, the latch means of the locking mandrelbeing camrned resiliently inwardly against a biasing means (not shown)in the mandrel as the valve is lowered into the pocket. The latch meansis moved outwardly into the locking recess by the biasing means toreleasably hold the valve in position in the pocket.

The upper and lower sealing means 57 and S9 seal# ingly engage the borewalls 87 of the lower pocket sec- 'tion above and below, respectively,the ports 77 in the wall of the pocket and direct lifting gas enteringsaid ports to the slots in the body of the valve.

The valve then functions in the same manner as the valve 10, previouslydescribed. That is, the well fluids enter the open lower end of thetubing and rise therein as determined by the formation pressure. Theformation lluids may enter the pocket through the discharge port of thepocket and through the upper end of the pocket but are prevented fromflowing outwardly through the ports 77 in the wall of the pocket by theupper and lower seal means of the gas lift valve. The cheek valve 47 ofthe gas lift valve prevents ow upwardly through the valve.

Lifting gas may then be introduced into the annular space between thetubing string and the casing string C and enters through the ports 77 ofthe pocket whereupon it is directed to the slots 20 ofthe gas lift valveby the seal means S7 and 59. If the lifting gas pressure exceeds thepre-set or pre-loaded pressure in the chamber of the valve, the controlsleeve V30 moves inwardly to open the slots, whereupon the gas ilowsdownwardly through the valve and through the discharge port 78 into thetubing string to lift the well uids in lsaid tubing string.

When the gas pressure in the annular space falls below the pre-setcharging pressure in the chamber, the control sleeve returns to itsnormally closed position to close the slots 20 of the valve, the checkvalve also closi'ng to prevent reverse flow through the valve.

A number of landing nipples may be included at spaced intervals in thetubing string, whereby a plurality of gas lift valves may be mountedtherein. The gas lift valves at different levels in the tubing may beset to operate at different pressures, if desired; and, any of thevalves may be installed in or removed from any landing nipple by meansof a exible line operating mechanism without disturbing any of the othervalves or landing nipples in a manner already known in the art.

It will be seen that the gas lift valve of the invention is adaptable toinstallation in a landing nipple, whereby the valve can be removed andreplaced without disturbing the tubing string in the well. Further, itwill be seen that the gas lift valve of this embodiment functions inexactly the same manner as the valve of the lrst embodiment and with thesame advantages of operation and construction.

While an eccentric or offset mounting of the gas lift valve has beenshown and described, obviously the valve or valves could be removablymounted in landing nipples concentric with the tubing bore.Additionally, the gas lift valve could be permanently mounted inside anipple in the tubing string, if desired.

The foregoing description of the invention is explanatory only, andchanges in the details of the construction illustrated may be made bythose skilled in the art, within the scope of the appended claims,without departing from the spirit of the invention.

What is desired to be secured by Letters Patent is:

4il. A ow device including: a housing having a bore having an loutlet atone end andrprovided with lateral port means between the exterior of thehousing and its bore spaced longitudinally of .the housing from theoutlet; closure means mounted in the housing bore for controlling ow ofuid through said lateral port means, said closure means comprising adeformable hollow member having a substantially cylindrical tubularportion closed at one end, said cylindrical portion having its exteriornormally in a position engaging the interior of the housing so as toclose said lateral port means; and means carried bysaid housing engagingsaid one end of said hollow member to limit movement of said one end ofsaid hollow member in one direction and providing a closed pressurefluid chamber communicating with the interior of said hollow member,said chamber and the interior of said hollow member being adapted toreceive a compressible fluid under pressure, said closure member beingdeformable to open said port means to permit liuid ow therethrough.

2. A gas lift valve according to claim l having a support means carriedVby said housing and engaging said one end of said closure means toprevent movement of said one end in a direction opposite to said onedirection. 3. A gas lift valve according to claim l having a supportmember carried by said housing, said support member having a concaveupper surface engaging said one end of said closure means to preventmovement of said one e'nd of said closure means in a direction oppositeto said one direction.

4. A gas lift valve according to claim 3 wherein said support member isprovided with a plurality of circumferentially spaced longitudinal slotsin the outer surface thereof to permit ow of fluids therepast.

5. A ow device including: a housing having a bore having an outlet atone end and provided with lateral port means between the exterior of thehousing and its bore spaced longitudinally of the housing from theoutlet; closure means mounted in the housing bore for controlling ow offluid through said lateral port means, said closure means comprising adeformable hollow member having a substantially cylindrical tubularportion closed at one end, said cylindrical portion having its exteriornormally in a position engaging the interior of the lhousing so as toclose said lateral port means; and means carried by said housingengaging said one end of said hollow member to limit movement of saidone end of said hollow member in one direction and providing a closedpressure Huid chamber communicating with the interior f said hollowmember, said chamber and the interior of said -hollow member beingfilled with a compressible Huid, said closure member being deformable toopen said .port means to permit fluid ow through said port means, boreand outlet.

6. A flow device including: a housing having a bore having an outlet atone end and provided with lateral port means between the exterior of thehousing and its bore spaced longitudinally of the housing from theoutlet; closure means mounted in the housing bore for controlling flowof uid through said lateral port means, said closure means comprising ayieldable hollow member having a substantially cylindrical tubularportion closed at one end, said cylindrical portion having its exteriornormally in a position engaging the interior of the housing so as toclose said lateral port means; and means carried by said housingengaging said one end of said hollow member to limit movement of saidone end of said hollow member in one direction and providing a `closedpressure iluid chamber communicating with the interior of said hollowmember, said chamber and the interior of said hollow member providingmeans for receiving a compressible fluid under pressure in excess ofatmospheric, said closure member being yieldable to open said .portmeans to permit uid ow through said port means, bore and outlet.

7. .A ow device including: a housing having a bore having an outlet 4atone end and .provided with lateral port ea's between the exterior of thehousing and its bore spaced longitudinally of the housing from theoutlet; closure means mounted in the housing bore for controlling ow ofiluid through said lateral port means, said closure means comprising ayieldable hollow member having a substantially cylindrical tubularportion closed at one end, said cylindrical portion having its exteriornormally in a position engaging the interior of the housing so as toclose said lateral port means; and means carried by said housingengaging said one end of said hollow member to limit movement of saidone end of said hollow member in one direction and providing a closedpressure fluid chamber communicating with the interior of said hollowmember, said chamber and the interior of said hollow member beingcharged with a compressible iluid at a predetermined superatmosphericpressure, said closure member being yieldable to open said port means topermit iluid flow therethrough.

8. A ow device including: a housing having a bore having an outlet atone end and provided with lateral port means between the exterior of thehousing and its bore spaced longitudinally of the housing from theoutlet; an elongate yieldable resilient substantially cylindricaltubular closure means closed at one end mounted in the housing bore andhaving its cylindrical exterior normally disposed in a position engagingthe interior of the housing at said lateral port means so as to closesaid lateral port means; and means carried by said housing engaging saidone end of said closure means to limit movement of said one end of saidclosure means in one direction and providing a closed pressure fluidchamber communicating with the open end of said tubular closure means,said chamber and the interior of the tubular closure means being adaptedtovreceive a compressible fluid under pressure to yieldably maintainsaid closure means in its port means closing position, said closuremeans being yieldable in response to uid pressure in said lateral portmeans to open said port means to permit fluid ow through said portmeans.

9. A ow device including: a housing having a bore having an outlet atone end and provided with lateralA port means between the exterior ofthe housing and its bore spaced longitudinally of the housing from thevoutlet; an elongate yieldable resilient substantially cylindricaltubular closure means closed at one end mounted in the housing bore andhaving its cylindrical exterior normally disposed in a position engagingthe interior of the housing at said lateral por-t means so as to closesaid lateral port means; and means carried by said housing engaging saidone end of said closure means to limit movement of said one end of saidclosure means in one direction and providing a closed pressure fluidchamber communicating with the open end of said tubular closure means,said chamber and the interior of the tubular closure means being adaptedto receive a compressible uid under pressure to yieldably maintain saidclosure means in its port means closing position, said closure meansbeing yieldable in response to fluid pressure in said lateral port meansto open said port means to permit fluid ow through said port means; anda back pressure valve in the bore of the housing adapted to cl-ose thesame against back flow from the outlet to the lateral port means,whereby said back flow is prevented from acting against said closuremeans.

10. A gas lift valve including: a tubular body having lateral portscommunicating the exterior thereof with the interior thereof; aresilient hollow cup-like closure means closed at one end mounted insaid body means supporting said closure means in said body positioningthe exterior of said closure means to engage the inner wall of saidtubular body adjacent said ports, said supporting means engaging saidone end of said closure means to Ilimit; movement of said one end in onedirection, said closure means being movable from such engaging positionto control the ow of uid through said may flow therethrough; and meansfor maintaining a predetermined pneumatic pressure within said hollowcup-like closure means to normally hold said closure means -in positionengaging the inner wall of said body and closing said ports.

11. A well device including: a well pipe; a tubular body installed onsaid well pipe and having lateral port means communicating the exteriorof said body with thev interior of said body; hollow cup-like closuremeans closed at one end constructed lof flexible, resilient materialmounted in said body adjacent said port means; means supporting saidclosure means in said body with its exterior normally in closingengagement with the interior of said body at said .port means saidclosure means being contractable away from said port means to controlthe flow of iluid through Isaid port means, said support-ing meansengaging said one end of said closurel means to limit movement of saidone end in one direction; a flow passageway extending from the interiorof said port means in said body and adapted when said body is installedon said well pipe to communicate with inlet means in said well pipewhereby fluids entering said valve may flow therethrough into said wellpipe; and pressurizing 'means for maintaining a predetermined pneumaticpressure on the interior of said hollow closure means to normallyresiliently maintain said closure meansl in closing position, saidpressurizing means including a sealed chamber on said body havingcommunication with the interior of said hollow closure means andchargeable with a pneumatic fluid to said predetermined pressure'.

12. A well dev ice including: well pipe; a tubular body installed onsaid Well pipe and having lateral port means communicating the exteriorof said body with the interior of said body; hollow cup-like closuremeans constructedof flexible, resilient material closed at one end andvmounted in said body adjacent said port means; means` supporting saidclosure means in said body with its exterior normally in closingengagement with the interior of said body at said port'means saidclosure means being contractable away from said port means to controlthe flow of uid through said port means, said supportingA means engagingsaid one end of said closure means to limit movement of said one end inone direction; a ow passageway extending from the interior of said portmeans in said body and adapted when said body is installed on said wellpipe to communicate with inlet means in said well pipe whereby flu-idsentering said valve may flow vtherethrough into said well pipe;pressurizing means for f maintaining -a predetermined pneumatic pressureon the interior of `said lhollow closure means to normally re- 'Vsiliently maintain said closure means in closing position,

said pressurizing means including a sealed chamber on said body havingcommunication with the interior of said hollow closure means andchargeable with a pneu-V matic Huid to said predetermined pressure; andcheck valve means in said ow passageway closing against iiuid flow fromsaid well pipe back through said body, whereby such back flow isprevented from acting against said closure means.

13, A well device including: a well pipe; a tubular body installed onsaid well pipe and having lateral port means communicating the exteriorof said body with the interior of said body; hollow cup-like closuremeans constructed fof flexible, resilient material closed at one end fmounted in said body adjacent said port rnean-s; means supporting saidclosure means in said body with its exterior normally in closingengagement with the interior of said body at said port means, saidclosure means being contractable away from said port means to controlthe flow of fluid through said port means, said supporting meansengaging said one end of said closure means to limit movement of saidone end of said closure means in one direction; a flow passagewayextending from the im terior of said port means in said body and adaptedwhen said body is installed on said well pipe to communicate with inletmeans in said well pipe whereby uids entering said valve may flowtherethrough into said well pipe; pressurizing means `for maintaining apredetermined pneumatic pressure on the interior of said hollow closuremeans to normally resiliently maintain said closure means in closingposition, said pressurizing means including a sealed chamber on saidbody having communication with the interior of said `hollow closuremeans and chargeable with a pneumatic fluid to said predeterminedpressure; and check valve means including a cup-shaped memberconstructed of exible resilient material mounted `in said passageway,the concave end of said cup-shaped member opening away from the closuremeans and resiliently sealingly engaging the walls of said passageway,whereby back ow through the body to act on said hollow closure means isprevented.

14. A gas lift valve including: a body having a longitudinal boreforming a passageway therein; lateral port means in said body providingcommunication between the exterior of said body and said passageway at apoint spaced from the ends of said body; outlet port means in said bodyspaced from said lateral port means and providing communication betweensaid passageway and the exterior of said body; an elongate tlexibleresilient substantially cylindrical tubular closure member closed at oneend mounted in the bore of said body, said closure member having itscylindrical exterior normally disposed in a position engaging the borewall of said body across said port means and deformable away from saidbore wall and port means to permit and control the flow of fluidsthrough said port means; means supporting said closure member in saidbody and engaging said one end of said closure member to limit movementof said one end in one direction; and means for maintaining apredetermined pneumatic pressure in said tubular closure member tonormally yieldably maintain said closure member in port closingposition.

15. A gas lift valve including: a body having a longitudinal boreforming a passageway therein; lateral port means in said body providingcommunication between the exterior of said body and said passageway at apoint spaced from the ends of said body; outlet port means in said bodyspaced from said lateral port means and providing communication betweensaid passageway and the exterior of said body; an elongate tlexibleresilient substantially cylindrical tubular closure member closed at oneend mounted in the bore of said body, said closure member having itscylindrical exterior normally disposed in a position engaging the borewall of said body across said port means and deformable away from saidbore wall and port means to permit and control the ow of uids throughsaid port means; means in said body engaging said one end of saidclosure member to limit movement of said one end in one direction; and asealed chamber in said body communicating with the interior of saidclosure member, said chamber being chargeable with a pneumatic fluid toa predetermined pressure to normally yieldably maintain said closuremember disposed in port closing position.

16. A gas lift valve including: a body having a longitudinal boreforming a passageway therein; lateral port means in said body providingcommunication between the exterior of said body and said passageway at apoint spaced from the ends of said body; outlet port means in said bodyspaced from said lateral port means and providing communication betweensaid passageway and the exterior of said body; an elongate :llexibleresilient substantially cylindrical tubular closure member closed at oneend mounted in the bore of said body, said closure member having itscylindrical exterior normally disposed in a position engaging the borewall of said body across said port means and deformable away from saidbore wall and port means to permit and control the ow of iluids throughsaid port means; means supporting said closure member and engaging saidone end of said closure member to limit movement of said one end in onedirection; a sealed chamber in said body communicating with the interiorof said closure member, said chamber being chargeable with a pneumaticuid to a predetermined pressure to normally yieldably maintain saidclosure member disposed in port closing position; and check valve meansin said passageway intermediate said lateral port means and said outletport means and between said closure member and said outlet port means,said check valve means opening to permit tlow of tluids from saidlateral port means through said passageway to said outlet port means butclosing to flow of fluids from said outlet port means to said lateralport means, whereby fluids are prevented from flowing from said outletport to act against said closure means.

17. A gas lift valve for use in a landing nipple having aperture meanscommunicating the exterior thereof with the interior thereof, said valveincluding a tubular body having lateral port means providingcommunication between the exterior of said body with the interior ofsaid body; an elongate tubular closure means constructed of flexibleresilient material mounted in said body adjacent said port means, saidclosure means having a substantially hemispheric integral closed endportion of the same material as said closure means and its exteriorportion spaced from said substantially hemispheric end portion normallydisposed in a position engaging the interior wall of the body acrosssaid port means and deformable away from said port means to control theow of fluid through said port means into said body; means carried by`said body engaging said closed end portion to limit movement of saidclosed end portion in one ydirection said body having means on itsexterior providing grooves adapted to receive sealing means on theexterior of said body spaced above and below said port means, saidgrooves being so spaced on said body that when said sealing means isdisposed in said grooves said sealing means is sealingly engageable withthe walls of a landing nipple above and below said aperture means whensaid body is `disposed in a landing nipple whereby the dow of uidsthrough said aperture is directed into said port means; a ow passagewayin said body providing communication between the interior ends of saidport means and the exterior of said body at a point spacedlongitudinally from said port means a distance greater than the nearersealing means whereby uids entering said valve through said port meansmay ow therethrough into the interior of the landing nipple; andpressurizing means for maintaining a predetermined pneumatic pressure onthe interior of said closure means to normally resiliently yieldablymaintain said closure means in port means closing position.

References Cited in the le of this patent UNITED STATES PATENTS2,642,889 Cummings June 23, 1953 2,731,977 McGowan Jan. 24, 19562,790,395 Garrett et al Apr. 30, 1957

